OK, after a bit or searching around and head scratching I think I picked up a couple more things from this chaper:
1) The technique that Silverman used was called the "arrogant" spark. Looks like a literal translation, so probably something like superior spark would be better.
2) Silverman was the creator of the 3 special techniques, and he created the mural? They were originally designed as killing moves. Suguru's version differs from his and Nemesis's as it isn't fatal.
3) He also mentions that Suguru has unexpectedly exceeded the power of the origin. Maybe Nemesis has to??
4) Silverman laments over the talent that has been lost by the commandment that defeated perfects must commit suicide.
5) He remembers Peekaboo and hopes he comes so he can speak with him?